BOI 



148 



BOI 



capable of being ground so fine, and to 

 mix with the oil so entirely as to seem one 



thick oil of the same colour. The word 



body is frequently used to denote the main 

 or principal part ; e. g. the body of a. pump, 

 which is the thickest part of the barrel or 

 pipe ; the body of a coach, &c. It is also 

 used to designate a number of individuals 

 or particulars united ; e. g. the legislative 

 body. "\Ve also speak of bodies corporate, 

 bodies politic, &c. 



BODY PLAN, in the language of naval 

 draftsmen, an end view, showing the 

 contour of the sides of the ship at certain 

 points of her length ; and since the sides 

 are exactly alike, the left half is made to 

 represent the vertical sections of the 

 after-part of the body, and the right half 

 those of the forepart. The 

 base of the projection is 

 the midship section, called 

 the dead-flat, and within 

 this the other sections are 

 delineated. 



Boo, an Irish word sig- 

 nifying soft, and applied to 

 a quagmire covered with 

 herbage. It is defined by 

 marsh and morass ; but dif- 

 fers from a marsh, as a part 

 from a whole. Bogs are 

 too soft to bear a man's 

 weight : marshes are less 

 soft, but very wet; swamps 

 are spongy grounds which 

 are often mowed. 



BOG'-BERRY , thecranbenry 

 or marsh whortleberry (vac- 

 cinivni oxycoccos) which is 

 common in peat-bogs. 



BOG'-IROJJ-ORE, 1 an iron ore peculiar to 



BOO'-ORE, J boggy land. " At the 



bottom of peat mosses there is sometimes 

 found a cake or pan of oxide of iron," to 

 which this name is given. It is probably 

 derived from the decayed vegetables, of 

 which most of the moss is composed. 



BOG'-RUSH. 1. A name common to all 

 the plants of the genus Schtenus, most of 

 which inhabit spongy grounds. Bonn 



enumerates three British species. 2. 



A bird, a species of warbler of the size of 

 a wren, common among the bog-rushes of 

 Schonen in Sweden. 



BOO-SPAV'IN. In farriery, an encysted 

 tumour on the inside of the hough, con- 

 taining a gelatinous matter. 



BOO'-WHORT, the bilberry or whortle- 

 berry, common in boggy grounds. 



BOHE'A, a species of black tea (see TEA), 

 named, according to G rosier, from a 

 mountain in China, called Vou-y or Voo-y. 



BOIL, an inflammatory, circumscribed, 

 and very painful swelling immediately 

 under the skin, which always suppurates, 

 and sooner or later discharges its con- 

 tents. The word is perhaps from the 



Goth, buila, rage, madness, as its Latin 

 synonym, fttruncitlus, is from the verb 

 fu.ro, to rage. 



BOIL'ER, a large pan or vessel of iron, 

 copper, or brass, used in distilleries, pot- 

 ash works, and the like, for boilins large 

 quantities of liquor at once. The same 

 name is given to the vessel in which 

 steam is generated for the supply of a 

 steam-engine. This boiler is usually 

 formed of plates of copper or malleable 

 iron rivetted together, so as to be per- 

 fectly air-tight, and in shape oblong, its 

 sides and bottom arched inwards, but its 

 top curved outwards. The figure is a lon- 

 gitudinal section : aa is the boiler, bb the 

 flues, c, the chimney, d, the ash-pit, <, 

 an opening to receive any ashes which 



may be carried over the furnace bars, /, 

 the fire-place, g, the man-hole, in the 

 cover of which there is a valve which 

 opens inwards, h, steam-pipe leading to 

 the engine, ijk, the safety-valve, with 

 its lever and weight, I, a stone-float ba- 

 lance by the weight m, both being at- 

 tached to the leyer nop, the fulcrum of 

 which is at o. To the centre of this lever 

 is also attached the small rod which works 

 the small valve fixed in the bottom of the 

 top part of the feed-pipe, qrt. The force 

 of the steam in the boiler causes the 

 water to rise in the pipe and act upon the 

 float opposite t, connected by a chain 

 passing over the pulleys, t>, to the dam- 

 per w, which is capable of moving up 

 and down in guides, and of closing and 

 opening the passage, where the flue enters 

 the chimney, xy, are the guage-cocks for 

 ascertaining the height of the water in 

 the boiler. 



BOIL'INO POINT, the temperature at 

 which a fluid begins to boil and assume 

 the gaseous state in contradistinction to 

 freezing-point. Both points are different 

 in different fluids, but constant in eapH 



